Bulletin of the Museum of Comparative Zoology AT HARVARD COLLEGE. Vol. LIV. No, 6. MAMMALS OF THE WEST INDIES. By Glover M. Allen. CAMBRIDGE, MASS., U. S. A.: PRINTED FOR THE MUSEUM. July, 1911. No. 6. — Mammals of the West Indies. By Glover M. Allen. Introduction. During August and September of 1910 the writer made a small collection of mammals in the island of Grenada. The study of these and of other West Indian specimens in the collection of the Museum, suggested the preparation of a list of mammals known to occur in the West Indies, with a summary of their recorded distribution and not its zoogeographical bearing. Most of the conclusions reached are new, but are of value in connection with similar studies of other groups of animals. The evident gaps in our knowledge of the dis- table tribution of many species is made evident by the summary is taken given. Three new island races are described. No account in this paper of the aquatic mammals nor of domestic animals that have become more or less feral in some of the islands. The bibli- ography includes most of the important papers dealing with the mammals of the West Indies. It is a pleasure to extend thanks to His Honor Robert S. Johnstone, now Chief Justice at Grenada, to whom I am indebted for unfailing hospitality and effective assistance while collecting in that island, as well as previously during a visit to the Bahamas. Zoogeographical Relations. Much has been written on the derivation of the West Indian land fauna, especially as to that of its molluscs, amphibians, reptiles, and birds. Hitherto but little attempt has been made to examine care- fully the distribution of its mammals with a view to discovering evi- dence in confirmation or disproof of current theories regarding former land bridges, or other means of immigration. No doubt this is mainly due to the fact that there are comparatively few terrestrial species of mammals in the Antillean region; and the distribution of these is,- in the main, so limited, or so imperfectly known, as to be of slight aid. It has been customary to ignore, more or less completely, the facts offered by the geographical distribution of bats in island faunas on the ground that they are capable of flying widely oversea, and hence 176 bulletin: museum of comparative zoology. might readily populate unoccupied ground. Among certain genera it is probable that such a method of distribution may, in sporadic instances, obtain. That it is frequent and normal, however, is equally improbable. It is well known that certain species of the temperate zones retire from the higher latitudes of their summer range to winter in more equable climes. In the course of such migrations they are occasionally met with far from land. This seasonal migration for example, is probably accountable for the occurrence of Lasionycferis noctivagans among the Bermuda Islands. Large, strong-flying bats, such as the Old World flying-foxes, often make nightly forays of great length from their roosts to some favorite feeding-ground, and they may even conceivably visit islands within sight of their mainland haunts; but that oceanic islands are often populated in this way there is very little evidence. Indeed, the very fact that where bats are found in islands they have usually become more or less differentiated from their nearest neighbors, and this in a uniform and constant manner, is proof that such fortuitous methods of distribution as have been claimed for these animals are largely inoperative. Dobson (in 1879) seems to have been the first to insist on the erroneousness of this assumption as to the inutility of bats in zoogeo- " graphical study. For, he says, even if it be granted that the Chirop- tera possess great powers of dispersal, it is certain that quite nine- tenths of the species avail themselves of them in a very limited degree indeed, and it is significant that the distribution of the species is limited by barriers similar to those which govern it in the case of other species of mammals." He recalls also the possible transporta- tion of bats from place to place by vessels. The West Indies are beyond the winter range of the northern migratory bats; and, except possibly in the case of a few species to be mentioned, it is almost certain that the present chiropteran fauna of each island is quite stationary. The presence of the less strongly-flying species on the several islands may therefore confidently be assumed as evidence either that they reached these islands by following some former land bridge nearly or quite continuous, or that they are autochthonous. In the following discussion, the evidence of the terrestrial mammals will be first considered. Of these, there are included in the present list some thirty-seven species or subspecies. Eight of these may be at once dismissed as introduced by human agency, viz.: Oryctolagus cuniculus, Mus musculus, Epimys rattus, E. r. alexandrinus, E. norve- gicus, Mungos birmanicus, Cercopithecus mona, C. sabaeus. Possibly the deer occurring on Cuba should be added to this list. A compari- ALLEN: MAMMALS OF THE WEST INDIES. 177 son of specimens would show whether it were the same as that of Florida or Yucatan, or if it be really an insular race. Of the remainder we may distinguish, for convenience, two groups: those belonging to genera now known from the Antilles alone, and those belonging to genera that are also represented on the mainland of America. Those of the former group fall at once into two divisions, geographi- cally. The first contains Capromys, Plagiodontia, and Solenodon of the Greater Antilles; the second, Ainblyrhiza and Megalomys of the Lesser Antilles. A similar division may be made of the group of mammals that are insular representatives of known continental forms. Thus, in the Greater Antilles are: Megalonyx rodcns, a fossil ground sloth known from Cuba only, and Oryzomys antillarum, of Jamaica, an island representative of 0. couesi, of the neighboring Honduras peninsula. In the Lesser Antilles, from Tobago northward to and including St. Thomas, are: Didclphys marsupialis insularis and Marmosa cha/pmani, opossums both closely related to species of northeastern South America, and a nine-banded armadillo (Dasy- all of which natural pus) ; probably have not by means spread farther north than Grenada. The agouti (Dasyprocta), at least until very recently, occurred on practically all of the Lesser Antilles to St. Thomas. The possibility of human interference in carrying this much sought animal from island to island should, however, be kept in mind. The occurrence of Loncheres and Oryzomys in Martinique and St. Vincent respectively is of much interest. The former has been taken only once, but is known to the negroes of Martinique, so that it is possibly native. The latter, as in case of the opossums and the armadillo of the more southern islands, is closely related to a species of the neighboring mainland, and is quite different from that of Central America, whence evidently the Jamaican species was derived. There is every probability that, before the coming of the white man, Oryzomys was of more general distribution in the Antilles; but the introduction of the house and roof rats (Epimys) brought in a competitor against which the rice rat was unable to stand. Even yet, however, a careful search in the more inaccessible parts of some of the larger islands might discover, a few survivors. It is doubtful what significance may be attached to the recent discovery of a small race of raccoon in New Providence (Bahamas) and in Guadeloupe (Windward Islands). A third raccoon is known from Barbados, but its identity is still uncertain. Some have sup- posed that the silent dogs ("perros mudos") mentioned by the early Spanish explorers as kept by the natives of Haiti were really these 178 bulletin: museum of comparative zoology. raccoons, but such a possibility seems extremely remote. Feilden and others assume with some confidence that the raccoon on Barbados might readily have drifted thither from South America with some of the wreckage of trees and flotsam that is constantly borne to the windward shores of that island by the easterly currents of air and sea. On the other hand, it might readily have been introduced during the past four hundred years by the European invaders. Patrick Browne mentions the raccoon as among the mammals occasionally brought in captivity to Jamaica, but here it is not known to have escaped and established itself. The presence of the insectivorous genus Solenodon on both Cuba and San Domingo emphasizes the geographic relationship of the two islands. Evidently these primitive animals have been here for a very long period; so that not only have their congeners died out on the neighboring mainland, but they have themselves, through long isolation, become markedly differentiated on the two islands. The fact that their nearest living relative is Centetes of Madagascar need indicate nothing more than that both genera are surviving. primitive types of this widespread order that have been preserved in their island habitats, free from the keener competition with the more nu- merous mainland fauna. The fact that all the known fossil Insectivora of America are found north of Mexico, and that the order is appar- ently represented in South America by a very recent influx of North American types into the northern part of that continent is quite in line with the fact that Solenodon is found in the Greater Antilles only, and is quite absent from the Lesser Antilles, which, we may suppose, it would have had to reach from the South American mainland. The terrestrial mammals of the island of Tobago are so evidently derivatives of those in Trinidad that they are not here specially con- sidered.